Software Review: Sefaira

Almost 2 years ago, EHDD signed on as early adopters of Sefaira, a new energy modeling tool built specifically for architects to use in the early stages of the design process... also known as the holy grail. The team based in London and New York came to our office as part of a tour around the country to try to convince firms to buy into the program in exchange for an opportunity to provide feedback and input that would help develop the tool. I was skeptical at first, but after hearing the presentation and some very satisfactory answers to what I must admit was an onslaught of very specific and technical questions, EHDD signed on, and here's why.

There was some hesitation about the fact that Sefaira has built their own simulation engine. There are plenty of engines out there that are verified, like DOE-2, so why fix it if isn't broken? The short answer is that DOE-2 and other engines were built for very detailed, engineering based energy models, and the purpose of Sefaira was not necessarily to get the granularity achieved by compliance models, but rather to get quick results that let you compare the general impact of different strategies. Furthermore, Sefaira minimizes the number of inputs required to get meaningful results which greatly increases the ability of the architect to use the software.

Overall, I find the balance between control and specificity and ease of use to be very well achieved with Sefaira. The interface allows one to rely on automatic "typical" inputs for things like control temperature and lighting power density, but also allows a more sophisticated user to fine tune and control these inputs as well. This level of transparency and control is what is missing from free tools like COMFEN, and can be important in specialized building typologies.

At this point, I have not investigated the water tools very much, but the fact that they exist and are integrated into the program is great. This approach allows for a more holistic sustainable design, and the fact that building envelope, renewable resources, and water are all incorporated in one tool was very desirable. The software also creates highly graphic outputs which don't need any post processing to be legible, another rarity in the world of energy modeling. I still prefer to export the raw excel data and customize my own graphics, but the fact that it allows for both is also a huge step forward.

Sefaira is continually upgrading itself and adding new features, which is another positive sign. The industry changes rapidly, and generally, they are able to respond and update the software in a timely manner. One such recent addition, is the capability to perform overheating analysis, which is critical in the UK for code compliance. While this is not usually an issue in the US, the ability to simulate comfort as well as energy use will only improve our buildings as we move forward.

One drawback is that at this point Sefaira is only compatible with Sketch-up. When the software was developed several years ago, sketch-up was the go-to tool for architects during conceptual design. Now that the industry is moving towards Revit, Sefaira is less applicable as a seamless introduction to the design process, but they are working to remedy that and I am sure they will release a Revit plug-in soon.

6 Comments

Amy, all of us at Sefaira are proud to call EHDD an early adopter. It is visionaries like yourself who have guided us over the years. As head of product development for Sefaira, I'd like to provide some additional insight

We have recently launched US Department of Energy EnergyPlus as a 2nd engine to do thermal comfort analysis in Sefaira Concept. Unlike other software that deploy sophisticated energy modeling engines, our implementation of EnergyPlus autoscales with the complexity of your design, in order to balance speed of simulation and accuracy. This implies that as a designer, your design process is enhanced due to rapid simulations that enables iterative design.

Further, as you suggest, we are committed to enabling performance based design for all architects and this includes supporting all design platforms. While we are committed to building seamless integration with Revit, we offer tips to allow designers to analyze their Revit models using Sefaira Concept.

Sounds very cool. Amy, have you worked with Autodesk Vasari? I'm most familiar with it and Ecotect, and would love to hear a comparison between Sefaria and them.

Vasari is currently free, and it looks like it does many of the things that Sefaria does in terms of energy analysis, plus it integrates straight into Revit (it actually saves as .rvt files, and the interface is very similar to [but better than] Revit's Massing Environment. It's a lot of fun for conceptual modeling, and I've been decently impressed by the energy modeling for quick, preliminary design studies.

I know Autodesk has had accuracy issues with previous energy modeling software (cough, Ecotect, cough) that were a major focus for improvement in Vasari -- so I'd be curious to see how it and Sefaria compare in terms of accuracy.

Either way, it's always good to see that Autodesk has some form of competition, haha.

I believe Vasari is using Green Building Studio to perform energy analysis and this program does not allow for the amount of control of transparency I found with Sefaira. This issue always concerns me because if I don't know the data that is going into the simulation, how can I trust the data that is coming out of it? The solar analysis tools migrated from ecotect, however, are very useful!

Hi Amy, Carl Sterner from Sefaira here. It's been nearly a year since your review, so I thought a quick update might be in order. Since you wrote your review, we've released the following new features:

Integration with Autodesk Revit (direct analysis of .rvt files)

Real Time Analysis directly within SketchUp

Daylighting analysis & visualization (using Radiance & DAYSIM)

Daylight-based lighting controls, which lower lighting demand based on daylighting

Sefaira currently supports Revit 2013 and 2014, and will likely add support for more recent versions of Revit going forward. (Check back soon -- we move quickly.) Vasari is not supported; however, there's a workaround in which you can bring a Vasari model into Revit and use "mass by face" tools to create a model that can be analyzed.

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A discussion on everything to do with sustainable design. From renewable energy to implementing integrated design in professional practice. Case studies, article reviews and green building certification methods and additional resources will all be included.